In general, robots have been developed for the industrial purposes and played a role in part of factory automation. Recently, application fields of robots have further extended to development of medical robots, aerospace robots, and the like, and even home robots have also been manufactured.
Robot cleaners are typical examples of home robots and a type of home appliance which performs cleaning by sucking dust or foreign objects nearby, while traveling in a predetermined area.
However, when a robot cleaner passes through an irregular region such as a groove (or a recess) formed in a door sill, while performing cleaning or moving, a main wheel of the robot cleaner may be hindered (caught) by the groove, and thus, the robot cleaner cannot rotate to perform normal traveling.
In order to solve the problem, Korean Patent Laid-Open Publication No. 10-2006-0063407 proposes disposition of a support wheel greater than the width of the main wheel of a robot cleaner near the main wheel.
That is, when the robot cleaner passes through an upper portion of the groove, the support wheel is supported on the upper portion of the groove, thereby preventing the main wheel of the robot cleaner from being hindered by the groove.
However, the related art robot cleaner has a problem in that the support wheel should be additionally provided to solve the problem, and thus, a technique for solving the problem is required.